/* infutil.h -- types and macros common to blocks and codes
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
#ifndef _INFUTIL_H
#define _INFUTIL_H
#include <linux/zconf.h>
#include "inftrees.h"
#include "infcodes.h"
typedef enum {
TYPE, /* get type bits (3, including end bit) */
LENS, /* get lengths for stored */
STORED, /* processing stored block */
TABLE, /* get table lengths */
BTREE, /* get bit lengths tree for a dynamic block */
DTREE, /* get length, distance trees for a dynamic block */
CODES, /* processing fixed or dynamic block */
DRY, /* output remaining window bytes */
B_DONE, /* finished last block, done */
B_BAD} /* got a data error--stuck here */
inflate_block_mode;
/* inflate blocks semi-private state */
struct inflate_blocks_state {
/* mode */
inflate_block_mode mode; /* current inflate_block mode */
/* mode dependent information */
union {
uInt left; /* if STORED, bytes left to copy */
struct {
uInt table; /* table lengths (14 bits) */
uInt index; /* index into blens (or border) */
uInt *blens; /* bit lengths of codes */
uInt bb; /* bit length tree depth */
inflate_huft *tb; /* bit length decoding tree */
} trees; /* if DTREE, decoding info for trees */
struct {
inflate_codes_statef
*codes;
} decode; /* if CODES, current state */
} sub; /* submode */
uInt last; /* true if this block is the last block */
/* mode independent information */
uInt bitk; /* bits in bit buffer */
uLong bitb; /* bit buffer */
inflate_huft *hufts; /* single malloc for tree space */
Byte *window; /* sliding window */
Byte *end; /* one byte after sliding window */
Byte *read; /* window read pointer */
Byte *write; /* window write pointer */
check_func checkfn; /* check function */
uLong check; /* check on output */
};
/* defines for inflate input/output */
/* update pointers and return */
#define UPDBITS {s->bitb=b;s->bitk=k;}
#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
#define UPDOUT {s->write=q;}
#define UPDATE {UPDBITS UPDIN UPDOUT}
#define LEAVE {UPDATE return zlib_inflate_flush(s,z,r);}
/* get bytes and bits */
#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
#define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
#define NEXTBYTE (n--,*p++)
#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
#define DUMPBITS(j) {b>>=(j);k-=(j);}
/* output bytes */
#define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
#define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
#define FLUSH {UPDOUT r=zlib_inflate_flush(s,z,r); LOADOUT}
#define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
#define OUTBYTE(a) {*q++=(Byte)(a);m--;}
/* load local pointers */
#define LOAD {LOADIN LOADOUT}
/* masks for lower bits (size given to avoid silly warnings with Visual C++) */
extern uInt zlib_inflate_mask[17];
/* copy as much as possible from the sliding window to the output area */
extern int zlib_inflate_flush (
inflate_blocks_statef *,
z_streamp ,
int);
/* inflate private state */
typedef enum {
METHOD, /* waiting for method byte */
FLAG, /* waiting for flag byte */
DICT4, /* four dictionary check bytes to go */
DICT3, /* three dictionary check bytes to go */
DICT2, /* two dictionary check bytes to go */
DICT1, /* one dictionary check byte to go */
DICT0, /* waiting for inflateSetDictionary */
BLOCKS, /* decompressing blocks */
CHECK4, /* four check bytes to go */
CHECK3, /* three check bytes to go */
CHECK2, /* two check bytes to go */
CHECK1, /* one check byte to go */
I_DONE, /* finished check, done */
I_BAD} /* got an error--stay here */
inflate_mode;
struct internal_state {
/* mode */
inflate_mode mode; /* current inflate mode */
/* mode dependent information */
union {
uInt method; /* if FLAGS, method byte */
struct {
uLong was; /* computed check value */
uLong need; /* stream check value */
} check; /* if CHECK, check values to compare */
uInt marker; /* if BAD, inflateSync's marker bytes count */
} sub; /* submode */
/* mode independent information */
int nowrap; /* flag for no wrapper */
uInt wbits; /* log2(window size) (8..15, defaults to 15) */
inflate_blocks_statef
*blocks; /* current inflate_blocks state */
};
/* inflate codes private state */
typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
START, /* x: set up for LEN */
LEN, /* i: get length/literal/eob next */
LENEXT, /* i: getting length extra (have base) */
DIST, /* i: get distance next */
DISTEXT, /* i: getting distance extra */
COPY, /* o: copying bytes in window, waiting for space */
LIT, /* o: got literal, waiting for output space */
WASH, /* o: got eob, possibly still output waiting */
END, /* x: got eob and all data flushed */
BADCODE} /* x: got error */
inflate_codes_mode;
struct inflate_codes_state {
/* mode */
inflate_codes_mode mode; /* current inflate_codes mode */
/* mode dependent information */
uInt len;
union {
struct {
inflate_huft *tree; /* pointer into tree */
uInt need; /* bits needed */
} code; /* if LEN or DIST, where in tree */
uInt lit; /* if LIT, literal */
struct {
uInt get; /* bits to get for extra */
uInt dist; /* distance back to copy from */
} copy; /* if EXT or COPY, where and how much */
} sub; /* submode */
/* mode independent information */
Byte lbits; /* ltree bits decoded per branch */
Byte dbits; /* dtree bits decoder per branch */
inflate_huft *ltree; /* literal/length/eob tree */
inflate_huft *dtree; /* distance tree */
};
/* memory allocation for inflation */
struct inflate_workspace {
inflate_codes_statef working_state;
struct inflate_blocks_state working_blocks_state;
struct internal_state internal_state;
unsigned int tree_work_area_1[19];
unsigned int tree_work_area_2[288];
unsigned working_blens[258 + 0x1f + 0x1f];
inflate_huft working_hufts[MANY];
unsigned char working_window[1 << MAX_WBITS];
};
#define WS(z) ((struct inflate_workspace *)(z->workspace))
#endif
